Biological materials, such as cells, are used in numerous therapeutic, diagnostic and research applications. For example, stem cells may be administered to patients to obtain a desired therapeutic effect such as regeneration of tissue in vivo. In other situations, biological materials including cells may be administered for grafts, transplants, or other procedures.
To provide an effective preparation of the biological material, having sufficient concentration that may be administered to a patient or that may be useful for diagnostic and research purposes, it often is necessary to perform numerous and lengthy manipulations involving the material. For example, stem cells often are first separated and isolated from a tissue from which they are derived, such as muscle, blood or adipose (fat) tissue. The cells of such a composition then may have to be subjected to multiple rounds of purification, washing or other treatments before they can be introduced, such as by injection, into a patient. These procedures may require sequential transfer of the cells to different containers. They also may require further manipulations, such as to promote sedimentation. Each procedure preferably is performed aseptically or in a closed sterile system to limit or avoid the potential introduction of contaminating material or organisms into the composition. Alternatively, even if the cells will not be administered to a patient but, instead cultured in vitro, for example, they still may require extensive washing and concentration preferably in aseptic conditions.
Also, to be suitable for administration to a patient, it may be preferable for a preparation of biological material to be highly concentrated. This may permit a relatively small volume to be administered. For example, stem cell preparations of about 1×108 cells or more generally may be concentrated into a volume of less than five (5) mls for injection into a patient.
Although much work has been done in the field of tissue processing, there continues to be a need for advances in the field of processing biological material including in the areas of washing and concentrating material for subsequent therapeutic, diagnostic, research or other applications.